Figure 4. IMPα1 overexpression increases PER/TIM nuclear translocation in S2 cells.

(A and B) S2 cells were transiently transfected with pCaspeR-per-cfp, pCaspeR-tim-yfp, and pIZ-importin α1-VSV as indicated. (A) Cells were fixed 8 hrs after heat shock induction and then scored as nuclear (blue), cytoplasmic (orange), and uniform (both nuclear and cytoplasmic; gray). At least 100 cells were counted for each condition in two independent experiments. (B) Examples of each condition. The white arrowhead indicates nuclear envelope association of TIM (see also Results and S7B Fig.). (C) S2 cells were transfected as in Fig. 4A and then fixed every two hours after heat shock induction. S2 cells were counted as shown above.